This invention relates to a method and apparatus for supplying a transport fluid to auxiliary jet nozzles in a jet loom, wherein a weft thread is inserted into a weaving shed by using the jet of supplied fluid under pressure.
Generally, in a jet loom of such type, a main jet nozzle alone can not transport the leading end of the weft to a distance at a sufficient speed, so that a suitable number of auxiliary jet nozzles are provided on a reed to each produce a flow of air in cooperation with the main jet nozzle. However, if all the auxiliary nozzles are always operated, a large total consumption of air results. In order to reduce the total consumption, U.S. Pat. No. 3,705,608 has proposed to energize the auxiliary jet nozzles successively or in successive groups in time with the advancement of the leading end of the weft through the shed by providing each auxiliary nozzle or each group of auxiliary nozzles with a control device for opening and closing the corresponding nozzle or group of nozzles.
However, the auxiliary jet nozzles or groups of auxiliary jet nozzles are adapted to be operated successively in synchronism with a weaving motion of the loom. Therefore, when the loom is operated at a low speed or in one picking motion, the injection timing of the auxiliary nozzles is delayed with respect to the advancement of the leading end of the weft because at that time the weft is directed into the shed by the main jet nozzle at the same high speed as the normal operation. This causes a poor injection function of the auxiliary jet nozzles, which in turn causes the speed of the weft leading end to be expeditiously reduced to null and the weft leading end to be caught by an auxiliary jet nozzle, resulting in the weft not being inserted.
It is therefore a principal object of this invention to provide a method and apparatus for supplying a transport fluid to auxiliary jet nozzles in a jet loom, which assure that a weft insertion operation can be carried out without any miss even when the jet loom is being operated at a low speed or in one picking motion.